Heating system for refrigerator cars



April 13, 1937. c. D. NlvEN HEATING SYSTEM FOR REFRIGERATOR CARS FiledJune 2G, 1955 2 Sheets-Sheet 1 N E E E m m m m m m m m m m/ /2 m m mFig.- 2

April 13, 1937. C, D NNEN y 2,076,961

HEATING SYSTEM FOR REFRIGERATOR CARS Filed June 2e, 1935 2 sheets-sheet2 l: xfri 22 Fig. 3

Patented Apr. ,13, 1937 UNITED STATES WEISS-Hlt) DEC v.2l 1940 2,076,961

HEATING SYSTEDROR REFRIGERATOR Charles David Niven, Ottawa.,l Ontario,Canada Application June 26,

3 Claims.

This invention relates to a heating system for refrigerator cars and hasfor an object to provide a system which maybe installed, as a per-`marient andv self-'contained unit, on cars at present in use.

It is usual at the present time to place small heaters in the icebunkers of refrigerator cars during cold weather. Such heaters cannot bepermanently installed and moreover, they. have the disadvantage that thehot air rising therefrom collects near the top of the car, whichvresults in an uneven heat distribution, the lower part of the car beingtoo cold and the upper part too hot. Moreover, such heaters emit carbonmonoxide fumes which render the'atmosphere inside the 'car dangerous toworkmen.

It has been proposed to employ heaters using a liquid circulation systemas a permanent unit on cars but such heaters heretofore have been ofdesigns which either interfere with the loading space of the car oremploy some mechanical method of @forced circulation, which cannot beinstalled conveniently on cars at present in use.

The object of the present invention isthus to provide a heating systemwhich eliminates these and other disadvantages and which includes a`heater which is self-feeding and readily conltrollable. ,l

Further objects and advantages will appear from the followingdescription with reference to the accompanying drawings, in which,

Figure l is a diagrammatic top. plan of a refrigerator car, with partsremoved, showing heating system installed therein,

Figure 2 is a sectional side elevation of pertinent portions of theheating system,

Figure 3 is a sectional end elevation of the heater hopper, and

Figure 4 is a top planof the heater hopper.

In the drawings, I indicates the heater which is suitably supportedwithin a housing 2 underneath a refrigerator car 3 provided with theusual oor rack 4, 'floor 5, Z'bar 6 and steel sill 1. A suitable liquidcirculation means, which, for instance, may comprise a coil 8, is placedinside the heater, the ends of the coil being joined by means ofconnections 9 to riser and return pipes I0 which may be provided withcouplings II and which lead upwardly through the floor of the car to aheating coil I2 which extends around/the floor of the car underneath therack 4 as shown. The heater is provided with a repot I3 and a fuelinghopper I4 which is formed with a neck I5 extending down into thefirepot. The heater 455- also includes a grate I6, whiclrmay, forinstance,

1935, Serial No. 28,588

be of the conical type, as shown, a shaker handle I1 for shaking thegrate, an ash pit I8, an yash pit door I9 with a draught control 20, andan inspection door 2I communicating with the fire box.

The hopper I4 is loaded with fuel through a door 22 and the lowerportion of the hopper and neck I5 are insulated to some extent by theprovision of a surrounding space 23 formed by means of an outer casing24. The space 23 is for the purpose of protecting the fuel supplyv inthe hopper from hot combustion gases and is shown as an air space butobviously any suitable insulating method may be adapted for the purpose.A fuel cut-off door 25 may be provided in the hopper together with anoperating handle 25 therefor. 'Ihe handle 26 may be formed with a kneejoint 2'I which allows the handle to fall down. when open and thusprevents any possi-` bility of the cut-olf closing by the vibration ofthe train.

The waste combustion gases are led olf by means of an outlet or flue 28which is provided with a door 29 in which is formed a draught control30. A cowl 3| is provided at the flue opening for the `purpose ofensuring delivery of the gases when the car is in motion. It will benoted that air will enter either of two air suction passages 32 andemerge through the outer cowl opening 33 thus drawing with it the .wastegases and providing a positive escape therefor.

In view of the fact that the hopper door 22 must fit tightly in order toprevent the entrance of air into the hopper and consequently the prob--able ignition of the fuel therein, ice, which forms by condensation ofmoisture driven off from the charcoal by the warmth from the firepot,would prevent the door 22 from being opened unless means are providedfor preventing the condensed water from freezing. In the presentinstance this difficulty is overcome by leading the hot combustion gasesover the dor 22 as shown. The exposed portions of the repot I3 and'pipes I I) should be insulated as indicated at 34. It is vital to thesuccessful operation of this heating system that the fullest advantagebe taken of the possible thermal head that can be developed in thelimited head room available below the oor of the car. This isaccomplished as shown by thermal insulation 34 in adequate amountexteriorly of all parts ofthe heater adjacent to liquid containing partsand" also of connecting pipes, particularly of the riser pipe. 'Ihecooling of heated liquid in the riser pipe by the outside moving ,airhas been found by trial to destroy a large part of the thermal head andto actually stop and even reverse the circulation. Thermal insulationthus serves primarily to develop and conserve thermal head forcirculation and secondarily to prevent undue heat losses and consequentwaste of fuel. No forced or mechanical circulation or impracticableheight of heater is required to maintain the ow of heating medium.

An expansion means of usual type for the circulation system may beprovided as indicated at 35.

In operation, the hopper I4 is charged with a suitable fuel and a liquidplaced in the circulation system which includes the coil 8, pipes IIJand coil I2. It has been found that charcoal is a preferable fuel andthat an anti-freeze solution is particularly suitable for employment asthe circulating liquid in order to avoid the possibility of freezingduring cold weather. The hopper I4 and neck I5 form a magazine forself-feeding the charcoal to the flrepot below, the ash passing throughthe movable grate to the ash pit. The hot gases pass up around the coil8, thus heating the liquid therein and causing a circulation thereofthrough the pipes I0. The heating coil I2 being located under the iioorrack 4 and thus utilizing normally waste space, no encroachment on theloading space4 or icing compartments of the car is made. Moreover thedisposition of the heating medium adjacent the bottom portion of the carensures that all the heat entering the car is supplied from below, thuscreating the ideal conditions necessary to obtain an even heatthroughout the loading space.

The method of disposing of the combustion gases closely adjacent theheater by means of the cowl 3l is particularly convenient since theencoachment on useful space in or about the car is thereby avoided.

The hopper I4 is of substantial capacity and requires infrequentrefuelling. By suitably arranging the outlet and inlet draught controlsthe fire may be readily controlled and the necessity of constantlylighting and extinguishing the fire, as is usually the case with heatersat present in use, is largely overcome.

The location of the heater underneath the car enables it to beconveniently attended to in contrast with present practice.

Should it be necessary to clean out the repot, it is only necessary toclose the door and remove the' contents of the repot through door 2 Ithus avoiding the waste of fuel which occurs when the standard heater isdumped in order to extinguish it.

It will be understood that various embodiments of numerous details ofthe invention may be rounding said riser pipes and said heater adjacentthe liquid heating means, means for admitting fuel to the heater and acombustion gas discharge passage having its discharge opening locatedabove the insulation surrounding the heater and directly below the floorof the car, said passage being adapted to supply heat to the fueladmitting means to prevent freezing of condensed moisture thereon.

2. In a heating system for refrigerator cars, l

a heater located entirely outside of and directly below the floor of thecar, liquid heating means in the heater, liquid circulating pipesdirectly above the floor of the car, riser pipes connectingsaid liquidheating means and said liquid circulating pipes, means for preventingundesired 'reverse circulation of liquid due to the limited height ofthe heater and exposure to weather conditions comprising thermalinsulation surrounding said riser pipes and said heater adjacent theliquid heating means, a horizontal combustion gas discharge passagelocated above the insulation surrounding the heater and directly belowthe floor of the car, and a fuel charging door for the heater locatedwithin said discharge passage. i

3. In a heating system for-refrigerator cars, a heater located entirelyoutside of and directly below the floor of the car, said heaterincluding a horizontal combustion gas discharge passage also locatedbelow the floor of the car, a repot, a fuel feeding hopper having a neckcommunicating therewith, a fuel charging door located Within saiddischarge passage and communicating with said hopper, and-a casingsurrounding said neck and lower portion of the hopper to provide aninsulating space therefor, and a liquid circulating system includingheating means therefor in said heater and a heatin'gcoil locateddirectly above the floor of the car and insulating means for said systemadapted to prevent undesired reverse circulation of liquid due to thelimited height of the heater and exposure to weather conditions. f

CHARLES DAVID NIVEN.

